PITTSBURGH — Some days it's the offense that decides games, with its fancy throwing and blocking and clearing out for the run; other days belong to the defense — the work of raw and bandaged fists.

But every so often the gremlins creep up from under the earth and inject their nonsense into things. They puff their magic dust, and it swirls around and wacko things begin to happen. And a whole week of team meetings and neatly typed game plans get trashed as a result.

Quirk plays. Lightning bolts on a clear day. Last Sunday in Pittsburgh, the Steelers outquirked Minnesota.

They appeared at the top of the fourth quarter, in a 13-10 game, as Steeler runner Rashard Mendenhall went airborne near the Minnesota goal. Out jumped the ball, and it landed in Viking hands, and a by-the-book, fit-and-sputter affair suddenly turned into a freak show.

Brad Childress, the frazzled Viking coach, can tell you about it. Two hobgoblins stung his team in the form of late Steeler scores — defensive ones — and they dealt his club its first loss of the weird '09 season. Steelers 27, Vikings 17 ... Gremlins 2.

His quarterback was Brett Favre, and the gremlins got him in dramatic form: fumble-recovery-long return, then tipped pass-interception-long return. Both went for touchdowns.

"What are you going to do?" said Vikes DE Jared Allen. "You win some and you lose some. Their defense outscored our defense at the end of the game. I don't know what else to say. There's not much else we can do. We held [Pittsburgh's offense] to 13 points. That should be enough to win."

All day the Vikings played Pittsburgh tough. They messed with Ben Roethlisberger's reads and jammed up the Steeler run lanes. Their own offense had scored only 10 points, but when Favre came out and held the ball for nearly the entire fourth quarter, momentum bending his way, you figured Minnesota was going to eke out a delicious road win.

That was a weary Steeler defense he was facing. Favre had picked up his rhythm, and he was attacking the deep right sideline and mixing things around and burning what was left of the Pittsburgh legs. Over 10 minutes of Vikings possession came in that fourth quarter ... and 10 first downs. The Steeler defenders wouldn't admit it to the microphones, but they were coming apart.

"Favre was going crazy," said S Ryan Clark. "I had no idea where he was looking, where he was throwing the ball. He did an awesome job moving us around. He's like the Chris Paul of football. He was throwing no-looks, look-offs. Unbelieveable."

But the gremlins, when they're stirring, have a thing for the dramatic. They were dramatic on Favre, and now the Vikings are 6-1, and looking back over the years, both franchises have seen their mischief at work before.

At old Three Rivers Stadium it was Steelers over Raiders and the Immaculate Reception — the most notorious gremlin of all.

And Joe Gordon, Pittsburgh's long-time communications director, recalls an incident during a 1984 match at Indy. Very late on the clock, and it was 3rd-and-24 for the Colts.

"We'd dominated them," says Gordon. "It was 16-10, under a minute left. Then they threw a pass and one of our cornerbacks, Sam Washington, made a play on the ball. He actually batted it twice. Their receiver Ray Butler grabbed the rebound and scored on it — a 54-yarder. A total shocker. They beat us by a point.

"Chuck Noll will tell you it was the toughest loss of his career."

Up in Minnesota, the No. 1 diablo is the Hail Mary - from the famous playoff with Dallas ... Staubach to Drew Pearson and the famous push-off that beat the Vikings. Former All-Pro tackle Ron Yary reveals some underworld details from that gray winter day in '75.

"After Pearson scored that touchdown," says Yary, "I went onto the field and I started yelling at the official who made the call. I said 'We went the whole year to get to this game and we lose it because of a bad call — because of you.'

"I got right in his face and I could smell alcohol on his breath. When he went in at halftime, he must've been cold and started nipping the bottle. Who knows — that could've impaired his judgment during that game.

"I yelled over to Bud Grant, 'This guy's been drinking!' But I couldn't do anything about it, and neither could Bud. The official didn't like the accusations — or at least he didn't appreciate Yary mouthing off about it.

"I was a marked man after that," he says. "But I had to stand up for my team on the field because I was the captain and it was a bad call. I had gotten in their face, and [the officials] eventually came after me."

Payback came two years later — in the Super Bowl. Vikings versus Raiders, and the man across the line from him was a crazy named John Matuszak.

"I was really blocking Matuszak downfield," recalls Yary, "pushing him about seven yards back into the secondary. I did it twice in a row. Then that same official came up to me during a TV timeout and said that if I did that one more time he was going to call me for illegal man downfield.

"I said, 'Wait a second! I can block like that if I sustain my block and don't come off him until after the ball is thrown.'

"He said, 'I don't care. I'm going to call you for it anyway.'"

After the Heinz Field lights went dark, I hung around outside the walls, messing with a cigar, when a guy calling himself Psychic Mike mysteriously appeared to me. He offered a light. He also offered information crucial to the day's events.

"I can influence games," said Psychic Mike, "through good energy and bad energy. Back home I put negative energy on the Mets and Jets. I don't like them, and you see what happened to them.

"Today I had the good energy on Pittsburgh. Did you see the breaks they got? Did you see that stuff? That was me." Then, a short while later, he disappeared.

Now it was making sense. A day that started out by the book had suddenly gone strange. Psychic Mike and those odd little gremlins ... laughing and chirping, and slipping back under the grass.

Have you ever noticed how teams seem to make their own "Gremlins" good or bad? It seems like when a team is playing well, they seem to create their own good fotune, and even the ball bounces their way. I don't know what you call it, karma or the power of positive thinking, whatever; but it seems like the better a team plays the more good breaks they get, and vice versa.

That's why Tomlin has a specific name for these types of things: "Splash Plays". They make or break games, and he has a knack for finding players who are capable of making them. Like fat, slow Woodley....and "bust" Timmons.